MRC decoder - blinking headlight

[sparkyjay31]

Anyone know what would cause the headlight on my Roundhouse 4-4-0 with the infamous MRC sound decoder to do this?: The headlight comes on on even numbered speed steps, and goes off on the odd speed steps. I simply cannot figure out why!

[rrinker]

 The decoder is set for 14 speed steps. IE, the number you have in CV29 is wrong. One of the bits in the speed packet for 14 speed steps ALSO controls the headlights, so when you send 28 speed steps instead, that bit varies on and off as you go through the speed steps. Hence turnign the headlight on and off. You need to either adjust CV29 to allow 28/128 speed steps, or you need to set your DCC system to only send 14 speed steps to that loco address.

                                       --Randy